Main menu

How To: Replace Control Arm Bushings in an FD RX-7 – Part 2

May 16, 2017

How To, REsuper7Archives

The rear suspension is a little more involved as there are 7 bushings/pillow balls to replace compared to the 4 for the front. But before we get to that, a quick disclaimer (again): All the steps outlined in this blog post are simply a recap of my own personal experience and is in no way associated with Final Form USA. If you choose to follow any of the procedures i describe below, you do so at your own risk.

We’re going to start with replacing the wheel studs and wheel bearing. The first thing you need to do is press the hub out of the wheel bearing housing. I can’t remember exactly what size socket i used, but i think it was 32mm.

*On a side note, I’ve always heard that replacing the wheel bearings were a requirement when replacing the wheel studs on the hub, but i found out this was not necessarily true. In order to replace the wheel studs, you need to remove the hub from the wheel bearing housing. I was told that when you go to press out the hub it splits the wheel bearing in half with the bearing race sticking to the hub shaft. But for my driver’s side hub, i was able to press it out of the wheel bearing without separating the bearing (pictured above), so technically i could’ve replaced the studs and pressed it back into the wheel bearing without installing a new bearing, but since i already bought the bearings, i just went ahead and replaced it anyway.

After removing the hub, you can replace the studs using the same method we discussed in the previous post for the front hub.

To replace the wheel bearing, first you need to remove the large retaining ring on top of the wheel bearing with a pair of pliers. Pressing the wheel bearing out is pretty straight forward as shown below.

To install the wheel bearing, i just placed the wheel bearing on top of the housing, and using one of the arbor plates i pressed it down until the bearing was flush with the top of the housing.

From there, i put the old bearing on top of the new one, and the arbor plate on top of the old bearing, and pressed the bearing until it was fully seated in the housing. Once in, reinstall the retaining ring.

From there, you can press the hub back into the wheel bearing housing using the 1 7/16″ socket. Make sure you support the bearing from underneath as you’re pressing the hub in to make sure the hub is fully seated in the bearing.

With the hub done, it’s time to move onto the control arms.

On the UCA, there are three solid bushings and one pillow ball bushing to replace. Starting with the shock mount bushing, this one can be pressed out in either direction. Using the 1 3/16 inch socket simply press the bushing straight out into one of the receiving cups.

For the two inner control arm bushings there’s a lip on the outer face of the bushing, which means you can only press the bushing out using the reverse press method and a 32mm socket as pictured below. Luckily there’s enough room to fit a receiving cup around the bushing so you don’t have to do any extra cutting.

The two inner control arm SuperPro bushings press in easily by hand.

After lubing the metal pin and the inside of the bushing, press the pin into the bushing using a vice.

The shock tower bushing is a little tricky as there’s a raised lip on both sides so you need to use a vice to squeeze the bushing into the arm. Just make sure you lube the bushing to make it go in a little easier. Once the bushing is in you can install the pin using the vice.

All the pillow ball bushings are replaced the same way so the method used here can be repeated for the lower control arm pillow ball bushings. First you need to remove the rubber dust cover. Use a flat head screwdriver, put it through the center hole and pry the dust cover off from the edge/rim of the cover.

If you’re planning to reuse the dust cover, be careful not to tear it. If the cover is loose and you can see a gap as you move the pillow ball around, you should plan to replace the covers. After you remove the covers on both sides, you should see the retaining ring holding the bushing in from one side. Remove the retaining ring with a set of pliers and position the arm in the press with the retaining ring side facing down. Pictures of the dust cover and retaining ring are for the LCA and just for reference.

Use a 7/8″ socket to press the bushing down into a 1 7/16″ socket as the receiver like pictured below.

Before attempting to press the new pillow ball bushing in, make sure you clean out all the old grease. Then using a really thin coat of grease, line the inside of the housing with it to make pressing the bushing in easier. Make sure you can’t see any of the grease as you should only use a very minimal amount. I used 1 1/16″ inch socket to press the new pillow ball bushings in. Just make sure you position the bushing with the tapered side going in first and the side with the lettering facing up as you press the bushing in.

Once bushing is fully seated, reinstall the retaining ring, then put the new dust covers on the spacer and install the spacer and the dust cover at the same time. You should be able to press the dust seal in by hand, just make sure it’s fully seated. Repeat the same steps for the opposite side. If you’re using teflon-lined pillow ball bushings, do not add any grease, otherwise they will shorten the life of the bushing.

For the rear LCA you can just reference the pictures as the procedure is exactly the same as the rear UCA.

Most people don’t replace the large bushing in the rear LCA that bolts to the rear subframe, but since i was on a roll, i figured why not just replace all of them. The only tough pill to swallow is the hefty price tag at $80 – $100 per bushing, depending on where you get it from. This giant bushing can be a little tricky to replace because of the metal lip on one side of the bushing. It’s impossible to remove the bushing without cutting the lip, which also means once you press it in, you won’t be able to remove and reuse it on another arm, so make sure the arm you’re using is 100% before pressing it in. See below for a picture of what the bushing looks like new and you’ll see the aluminum lip that i’m referring to.

To remove the bushing, first you need to cut away the rubber lip sitting on top of the lip using a utility knife.

Once all the rubber has been removed you’ll be able to cut the metal lip, which is actually made out of aluminum so it’s fairly easy to cut. Some people cut a straight edge on either side of the bushing, but i prefer to just cut off all of the lip so i can use a receiving cup to press the bearing into.

Technically you could push the bushing out as pictured above by resting the two cut edges on a hard surface, but I find it a lot easier to press the bushing out using a receiving cup and it doesn’t take that much more effort to cut off the rest of the lip. To avoid cutting through the lip and hitting the control arm, using a dremel with a cut off wheel, make a cut roughly 80% deep all the way around the bushing, then use a flat head screw driver or chisel and a small hammer and tap the lip away from the control arm. Once you tap it far enough, the metal is soft enough where you can just bend it back and forth a couple of times until it breaks off.

Once the lip is removed, you can position it in press with a receiving cup holding the side where the lip used to be and use the 1 7/16” socket to press the bushing down into the cup.

Installing the large bushing is very straight forward, as long as you keep in mind a couple of things. First, don’t be tempted to use a socket that fits around the rubber posts and holds onto the very edge of the bushing lip. You won’t have enough leverage to press the bushing all the way in and the lip will deform before you can get it in. Once that happens, you’re out of luck and you’ll have to remove the bushing and replace it with another one. (Yes, unfortunately i am speaking from experience). I used the socket looking thing from the rented bushing kit and sat it on top of the rubber posts and pressed it in that way. The rubber posts will squish and deform as you’re pressing the bushing in, but once its fully seated and you remove it from the press it’ll look completely normal.

And with that bushing in, we’re done!…well, with one side. But now that you’ve had a chance to practice all the techniques outlined here, the other side should be a piece of cake. And that concludes our tutorial for replacing bushings in a 3rd Gen Mazda RX-7. Hope you found the posts useful and feel free to leave questions or feedback in the comments section below!